Sludges that contain oil and water are generated via a sort of movements and procedures on board ships, including sedimentation in tanks, tank dewatering techniques, and leaks or cleaning cycles in backflush filters and separators for treating fuel oil and lube oil. The pattern for combusting excessive density gas oils of bigger viscosity, as good as the use of residues as a fuel for medium-velocity diesel engines, also increases the production of sludge from both fuel oil and lube oil.

The construct up of those oil and water-containing sludges represents a enormous disposal concern. Options which have frequently been employed to maintain them comprise incinerating the sludge on board, or taking away it on land. Nevertheless, incineration is an steeply-priced process in view that the sludge has to be dewatered by way of evaporators and then mixed with priceless diesel oil to generate a combustible fuel. Disposal on land can be related to giant expenses, as the sludge has to be transported to a waste disposal website online, which in turn needs to be paid for.